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Prove that 4cos(2pi)/7dotcospi/7-1=2cos(...

Prove that `4cos(2pi)/7dotcospi/7-1=2cos(2pi)/7dot`

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Prove that 4cos((2pi)/7).cos(pi/7)-1=2cos((2pi)/7) .

Prove that: cos(pi/7)cos(2pi/7)cos(4pi/7)=-1/8,

Prove that: cos(pi/7)cos((2pi)/7)cos((4pi)/7)=-1/8

Prove that : cos(pi/7)cos((2pi)/7) cos((3pi)/7)=1/8

3.Prove that (i) "cos((2pi)/7)*cos((4pi)/7)*cos((8pi)/7)=1/8

Prove that: sin((4pi)/9+7)cos(pi/9+7)-cos((4pi)/9+7)sin("pi/9+7)=(sqrt(3))/2

Prove that cos(2pi)/(15)cos(4pi)/(15)cos(8pi)/(15)cos(14pi)/(15)=1/(16)

Prove that cos((2pi)/(15))cos((4pi)/(15))cos((8pi)/(15))cos((14pi)/(15))=1/(16)

Prove that cos((2pi)/(15))cos((4pi)/(15))cos((8pi)/(15))cos((16pi)/(15))=1/(16)

Prove that cos ((2pi)/7)+ cos ((4pi)/7) + cos ((6pi)/7) = - 1/2

ALLEN-BASIC MATHS,LOGARITHIM, TRIGNOMETRIC RATIO AND IDENTITIES AND TRIGNOMETRIC EQUATION -EXERCISE (S-1)
  1. If the value of the expression sin 25^@* sin 35^@* sin 85^@ can be exp...

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  2. Prove that (4cos^2 9^0-3)(4cos^2 27^0-3)=tan9^0dot

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  3. Prove that 4cos(2pi)/7dotcospi/7-1=2cos(2pi)/7dot

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  4. Let P(k)=(1+cospi/(4k)) (1+cos((2k-1)pi)/(4k)) (1+cos((2k+1)pi)/(4k))...

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  5. Evaluate (2cos4 0^(@)-cos2 0^(@))/(sin2 0^(@)

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  6. Solve cos^6(pi/16)+cos^6((3pi)/16)+cos^6((5pi)/16)+cos^6((7pi)/16)

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  7. Given that (1+tan1^@)(1+tan2^@)...........(1+tan45^@)= 2^n find n .

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  8. Prove that from the equality (sin^(4)alpha)/a+(cos^(4)alpha)/b=1/(a+b)...

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  9. If a leq 3 cos (theta+pi/3)+5cos theta+3 leq b, find a and b, where ...

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  10. The value of (cotθ+cosecθ-1)/ (cotθ-cosecθ+1) is

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  11. If x and y are real number such that x^2 +2xy-y^2=6, find the minimum...

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  12. If A+B+C=pi, prove that tan^2A/2+tan^2B/2+tan^2C/2geq1.

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  13. solve the equation for x , 5^(1/2)+5^(1/2 + log5 sinx) = 15^(1/2 + log...

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  14. Find values of theta satisfying sintheta+sin5theta=sin3theta such that...

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  15. Which of the following are the solutions of equation 2sin 11x + cos3x ...

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  16. Find all value of theta, between 0 & pi, which satisfy the equation;...

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  17. Find the general solution of the equation, 2+tanx.cot(x/2) +cotx.tan(x...

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  18. Determine the smallest positive value of x which satisfy the equation ...

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  19. Find the general solution of the trignometric equation 3^(1/2+log(3)(c...

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  20. Find the value of theta, which satisfy 3-2 cos theta-4 sintheta-cos 2...

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